Question: WHICH IS THE VOTING ROUND WITH THE MAXIMUM NUMBER OF BLANK VOTES
Paraphrase: Which voting round has the most number of blank votes?
SPARQL (Wikidata): select ?ent where { ?ent wdt:P31 wd:Q24097670 . ?ent wdt:P5045 ?obj } ORDER BY DESC(?obj)LIMIT 5 
Answer: Second round of French presidential election, 2017, Second round of Ukrainian presidential election, 2010, First round of Ukrainian presidential election, 1994, First round of French presidential election, 2017, Second round of Ukrainian presidential election, 1994